AUTHOR=Qin Cheng , Cheng Linming , Zhang Huanhuan , He Meiling , Shen Jingqin , Zhang Yunhong , Wu Ping 

TITLE=OsGatB, the Subunit of tRNA-Dependent Amidotransferase, Is Required for Primary Root Development in Rice

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 7 - 2016

YEAR=2016

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2016.00599

DOI=10.3389/fpls.2016.00599

ISSN=1664-462X

ABSTRACT=<p>A short-root rice mutant was isolated from an ethyl methane sulfonate-mutagenized library. From map-based cloning strategy, a point mutation, resulting in an amino acid change from proline to leucine, was identified in the fourth exon of a glutamyl-tRNA (Gln) amidotransferase B subunit family protein (<italic>OsGatB</italic>, LOC_Os11g34210). This gene is an ortholog of <italic>Arabidopsis GatB</italic> and yeast <italic>PET112</italic>. GatB is a subunit of tRNA-dependent amidotransferase (AdT), an essential enzyme involved in Gln-tRNA<sup>Gln</sup> synthesis in mitochondria. Although previous studies have described that cessation in mitochondrial translation is lethal at very early developmental stages in plants, this point mutation resulted in a non-lethal phenotype of smaller root meristem and shorter root cell length. In the root, <italic>OsGatB</italic> was predominantly expressed in the root tip and played an important role in cell division and elongation there. OsGatB was localized in the mitochondria, and mitochondrial structure and function were all affected in <italic>Osgatb</italic> root tip cells.</p>